DE19712817C2 - Process for the production of wire-shaped welding electrodes consisting of metals and / or alloys, as well as wire-shaped welding electrodes - Google Patents

Description

The invention relates to a method for producing wire-shaped, consisting of metals and / or alloys Welding electrodes according to the preamble of claim 1 and one produced by such a method wire-shaped welding electrode.

It is for the increasing automation of welding processes required that the necessary welding consumables in Wire form can be provided. For precision welding small diameter wires must be available. At However, various alloys are used to make wire in the known drawing process due to the material properties the alloy is not possible or only with increased effort. This applies, for example, to aluminum bronzes with aluminum kept greater than 8 percent by mass.

Low electrical conductivity and due to unavoidable High contact resistances of Legie caused by oxide layers rations also lead to self-welding when welding consuming electrodes for premature glow and / or for Decrease in arc intensity. This will Welding in lower layers with larger wall thicknesses as well Even welding through with thin walls is difficult or made impossible.  

For the overlay and joint welding of such kriti shear alloys, various processes have already been used Manufacture of self-consuming welding electrodes proposed several material components. This well-known The common feature is that the alloys are required in the composition only when the electrodes melt arise.

DE 31 28 640 A1 shows a welding wire for use as an electrode, this ver consisting of several together single wires. Anyone who used there Single wires contain different metallic components or materials. A core wire can also be provided around which the individual wires are wound helically.

The for the production of the welding electrode wire according to DE 31 28 640 A1 necessary procedures have significant disadvantages. So it is not possible to pull smaller wire through knives because the necessary for the drawing process Lubricant when pulling in the spaces between the Single wires penetrates and then not or only with considerable effort can be removed. Furthermore the arc burns in the case of electrodes formed in this way shape is not uniform because of the radially different and variable distribution of components different electrical and / or magnetic properties arise that lead to undesired current density variations. From above reasons mentioned are in the application of the known The result of welding electrode wire welding errors.

In the process of making an electrode from below different metals and / or alloys according to the teaching of DE 23 59 738 A1 turns a plated strip into a roll shaped, the resulting intermediate to is then pulled to the required diameter. The solution described there has the disadvantage that the The outer surface of the electrode is not closed, so that in the existing gap when pulling lubricant penetrates that  cannot be completely removed, which means that later Use welding errors are the result. More in the DE 23 59 738 A1 described solutions, such as wrapping one or more core wires, have the common after partly that the electrodes thus produced are not pulled can, so that it is impossible to use wires with lower through manufacture knives under economic conditions.

In addition, in welding technology at self-consumption electrodes known as cored wires. For the manufacture development of electrodes from alloys that are particularly heavy can be subjected to cold or hot forming, such as e.g. B. nickel or cobalt-based alloys, is in DE 35 42 663 A1 a filler metal and a method for Preparation described, in which powder atomized by inert gas a seamless pipe is filled and then pulled a compression of the powder takes place, whereby the included gas volume should be reduced.

The tube is not filled continuously, but instead it will put the powder in a tube wound on a reel with mechanical movement, d. H. Shake, filled. In which The procedure briefly cited above cannot be ensured be that the tube can be filled evenly. More after parts are the high cost of manufacturing the metal powder and the inevitable inclusion of gas inside the electrode. The trapped air can admit the Pull away and be replaced with an inert gas, however only the type of gas enclosed changes.

PCT WO 86/03716 A1 describes a method for welding wire manufacturing described. There is proposed a metal tied into a sheath to form a core made of powder and / or solid wires, whereby by drawing, rolling or hammering the diameter can then be reduced to form a metal composite at the same time. According to the teaching there, powder is always incorporated into the core brings to a bond between sheath and core wires when  Pull to achieve. The economy of the known The method is restricted in that the cored wires only can be drawn with small degrees of deformation and thereby already from a relatively small diameter to the shell formed band must be assumed. This is also the in the solution described above is not suitable, the Eliminate disadvantages according to DE 35 42 663 A1.

JP 1-154895 A describes a process for the production of Welding electrodes known, where there the optimization of The focus is on the quality of the arc during the welding process stands. In particular, a preformed inner wire, which has a flux from an outer tube shaped sheath. The outer shell is ver welding sealed, reducing the through knife by subsequent pulling is possible.

DE 34 03 046 C2 deals with the problem of welding a cladding tube with an inner strand of material. When designing core wires according to DE 195 23 400 A1 differentiates between a covering with a material chemical composition. In a Another embodiment according to DE 195 23 400 A1 has the core wire a multi-coated core. That core wire can be an at least simply coated cored wire, a coated core from a powder or at least a simple one coated solid wire. In the manufacturing process after DE 195 23 400 A1 initially uses two metal strips Generating the inner jacket or the outer jacket of a first one Pair of bending rolls fed and after another pair guided by bending rolls through a filling station, in which Powder for the filling core is introduced. The filling station another pair of bending rollers follows in the conveying direction, where two pairs of closing rollers make up the double-sheathed cored wire assemble and hand it over to the reel. Alternatively, a side-mounted one at the filling station Cored wire can be inserted.  

However, it has been shown that with a powder insert tapes not seen or only with significant quality losses are drawable. The same applies to multi-coated core wires. Here it is inevitable that the drawing agent in the extreme loads, especially in the drawing die in the casing inner penetrates with corresponding disadvantageous consequences when Use of electrodes produced in this way.

Overall, it remains to be seen that the known Welding electrodes manufactured in the process Welding technology for technical or cost reasons only in Could enforce special cases. So there is still before a significant need for widely usable Solutions for self-consuming electrodes made from a ver Bundle of several metals and / or alloys in wire form exist and also for conceivable applications on small Diameters are pullable.

It is therefore an object of the invention to produce a method provision of wire, of metals and / or alloys existing welding electrodes, which allows through a variety of different materials safely Pull out as a mechanically plated laminated wire form without special on a conventional wire drawing machine Precautions must be taken to get the one you want To achieve qualities, and the layered composite wire Welding electrodes in their application optimal properties, such as B. show a uniform burning of an arc.

The object of the invention is achieved on the process side with a teaching according to the features of claim 1 and with a wire-shaped welding electrode according to the Features of claim 5, wherein the subclaims at least practical refinements and developments include.

The laminated wire is produced by first a metallic bright cleaned belt continuously into one  Pipe shaped and without the usual welding process Filler metal is welded. As a welding process comes for example TIG, plasma, induction or laser welding in question. Before welding it into it not fully finished pipe continuously the pretreated, metallic bare core introduced, this Core of one or more compact wires and / or one Laminated wire made of several metals or alloys can exist. By subsequent forming together, e.g. B. by pulling or rolling, the shell and core become that Laminated wire mechanically plated. Then can the composite wire thus produced to the required end measurements are taken in the usual way. At the latest at this pulling to the desired diameter a mechanically clad laminate is formed or composite wire made of materials of core and coat with a view to the workability and the desired welding applications can be optimized is.

According to the method, the core is at least on the process side a longitudinal groove that can be formed by rolling in, each longitudinal groove of the receptacle each with an insert wire serves. Core and insert wire materials can different properties and / or different possess material compositions.

In one embodiment of the invention, the longitudinal groove has essentially a width which corresponds to the diameter of the Insert wire corresponds. The depth of the longitudinal groove is in a range of 0.7 to 1.0 times the diameter of the Insert wire. The longitudinal core described above Groove and insert wire can be covered with an inner sheath or be provided with an inner jacket, which then with the outer Coat is surrounded, the outer coat the mentioned tube made by welding with outer closed Surface forms. When dragging the this way prefabricated composite wire is the desired  Plating by appropriate connection of insert wire and longitudinal groove core as well as outer and inner jacket and core.

According to the method, the core can be a composite wire with an open or closed outer surface covering the inner shell forms, are prefabricated, for this purpose a core wire with longitudinal groove and insert wire made of different materials with one Coat that forms the inner shell. The inner shell is made of a second metal. The inner one Coat can in turn be made from a prefabricated, multi-layer clad ribbon to be molded.

The wire-shaped, made of metals and / or alloy existing welding electrode thus creates a layer ver fret wire with an outer one closed by welding Coat made of pullable material and one inside the Sheath arranged cold-formable core. Preferred the outer jacket is made of copper or copper alloys, wherein the core is a composite material that after the above mentioned method can be produced.

The total required for the composition Depending on the alloy behavior, elements are either in alloys the base material (e.g. nickel, tin or manganese in Copper) or integrated as individual components (e.g. aluminum or iron). So the core can be constructed as a composite wire, the z. B. from a jacket made of aluminum (aluminum alloy) and a core that contains other alloys in addition to copper contains elements such as Fe, Ni, Mn, Sn etc. The Al coat of the composite wire used as the core is formed from tape, the strip edges are either welded or not stay welded. It is shaped by either the tape spirally wrapped around the core or with a tube Longitudinal seam is profiled. Since the alloying of copper with Fe- Held greater than 2 mass percent practically no longer possible is an iron wire (steel wire) in the Core integrated.  

In summary, the electrodes consist of different ones Material components that are closed as a composite wire with a its outer surface. The composite wire contains an electrically conductive and pullable closed outer jacket and a good cold formable Core. The composition and structure of the jacket and core are the same chosen that the required mechanical properties the manufacture of the wire-shaped welding filler hand as well as optimal properties in the application and the desired usage properties of the alloy after Melting on the other hand can be guaranteed.

The outer jacket of the wire-shaped welding electrode is closed, so that no subsequent pulling Lubricant in the individual material components or the Gaps can get between these, making a high Level of uniformity is achieved and the inclusion of Gases is completely avoidable. By mechanical Plating the components behaves like the layer composite wire during further processing, in particular by Drawing and / or rolling like a compact, quasi-monolithic Material.

The invention is intended below with reference to exemplary embodiments play and explained in more detail with the help of figures become.

Here show:

Fig. 1 a cross section introduced by the sealed in a tube jacket core before plating;

Fig. 2 is a cross section through the wire-shaped welding electrode after the completed in a first drawing step plating;

Figure 3 is a cross section through the wire-shaped welding electrode with a core, unwelded inner and welded outer jacket after plating.

FIGS. 4a and 4b, a core cross section with longitudinal groove before and after insertion of an insert wire;

Fig. 5 shows a cross section through a wire-shaped welding electrode with insert wire and unwelded inner and welded outer jacket after plating and

Figs. 6a and 6b, the formation of an inner shell of a non-welded clad composite material before and after coating with a welded outer jacket.

Of essential technical importance in welding technology are alloys with at least 70 mass percent copper, 5 to 18 mass percent aluminum and other alloying elements such as Fe, Ni, Mn and Sn, the so-called aluminum composite bronze. These are due to their mechanical properties increasingly broad field of application. With increasing aluminum content, however, takes the cold from 7.5 mass percent aluminum formability of these alloys. The production of Then wire is made of such an alloy by drawing practically no longer possible. For this reason, according to Embodiment the welding electrode for aluminum more fabric bronze with higher Al contents from different Material components constructed so that the cold formability is given and on the other hand when melting the required alloy compositions surrender.

The individual components are made according to the required processing processing and usage properties selected and com trimmed.  

In one exemplary embodiment, the aluminum bronze welding electrodes are produced as composite wires in that, as shown in FIGS. 1 and 2, a core 2 is coated with copper or a copper alloy to form a jacket 1 . The jacket 1 guarantees good ductility with optimal electrical conductivity and a low contact resistance. The core itself can be a composite material (e.g. reference number 4 in Fig. 3).

Depending on the alloying behavior, the alloying elements are either alloyed into the base material, e.g. B. nickel, tin or manganese in copper, or quasi mechanically integrated as individual components, e.g. B. aluminum or iron. Thus, the core itself, as shown in FIG. 3, can be constructed as a composite wire which, for. B. contains a core material 4 which, in addition to copper, has further alloy elements such as Fe, Ni, Mn or Sn. This core material 4 is then surrounded by an inner jacket 3 made of aluminum or an aluminum alloy. The aluminum sheath 3 of the composite wire used as the core is formed from a strip, the strip edges either being welded or remaining unwelded.

The jacket 3 is formed by either winding the tape spirally around the core 4 or profiling it into a tube with a longitudinal seam.

Since the alloying of copper with Fe contents greater than 2 mass percent is practically no longer possible, an iron or steel wire is introduced into a corresponding longitudinal groove 9 of the core 6 with reference to FIGS . 4a, 4b and 5. FIG. 4a shows the design of the longitudinal groove 9 , with FIG. 4b then showing the state after the insertion wire 5 has been received in the longitudinal groove 9 of the core 6 .

In the cross-sectional view of a welding electrode wire according to FIG. 5, a core 6 with an insert wire made of iron or steel 5 is assumed, an inner jacket 3 made of e.g. B. aluminum or an aluminum alloy is provided. This structure is then surrounded by the outer jacket 1 , which has a closed surface.

The composition of the jacket 1 and the structure of the composition of the core 2 depend in each case on the desired alloy composition. In this way, a plurality of insertion wires 5 can also be molded into the core wire 6 .

In addition, the core 8 can , as shown in FIGS. 6a and 6b, be encased by a plurality of cladding layers 7 . The multilayer jacket 7 of the core 8 is formed in this case by forming a previously plated band.

In the embodiment illustrated with FIG. 3, aluminum bronze welding electrodes with a composition of 14 to 15 mass percent aluminum, 2 mass percent manganese, 1.5 mass percent iron, 2.5 mass percent nickel and the rest copper are assumed. The outer welded jacket 1 with a volume fraction of 24% and the core 4 with a volume fraction of 39.3 to 41.2% consist of a copper alloy with 2.35 mass percent manganese, 1.7 mass percent iron and 2.94 mass percent nickel . In between is an aluminum jacket 3 with an open longitudinal seam, which has a volume share of 34.8 to 36.7%.

The welding wire shown in FIG. 5 represents an aluminum bronze welding electrode with a composition of 14 to 15 percent by mass of aluminum, 3 to 5 percent by weight of iron and a remainder of copper. As described, a first, illustrated with FIGS. 4a and 4b, is used Core wire 6 is used, which consists of copper, into which the longitudinal groove 9 is rolled. The width of the longitudinal groove is approximately equal to the diameter of the iron insert wire 5 , the depth of the longitudinal groove 9 corresponding approximately to 0.9 times the diameter of the insert wire 5 . The insertion wire 5 is then rolled into the core 6 in a form-fitting manner. The copper core wire 6 has a volume fraction of 35 to 39%, the iron wire 2.5 to 4.3 volume percent. Then there is the aluminum jacket 3 ( FIG. 5) with an open longitudinal seam and a volume fraction of 34.8 to 36.7 volume percent. The longitudinally welded, closed outer jacket 1 consists of copper and has a volume fraction of 24 volume percent.

Claims (5)

1. A process for the production of wire-shaped, made of metals and / or alloys welding electrodes as composite wire with a closed outer surface, wherein in a continuous process a well-conductive, ductile metallic band is formed into a still open tube, a metallic, cold-formable within the tube The core is introduced and the tube is welded to a closed sheath, and after the tube has been welded, by pulling the sheath and core together to a desired diameter, the mechanically platied layered composite wire is formed, characterized in that one or rolled several longitudinal grooves who who the inclusion of one or more insert wires, the core and insert wire materials have different material compositions, and that the metallic strip before the tube forming and the core before insertion into the tube of an ob subjected to surface cleaning treatment. 2. The method according to claim 1, characterized, that the core as a composite wire with open or closed outer surface is prefabricated, with a core for this with longitudinal groove and insert wire from each different Materials with a multi-layer coat made of difference metal is encased.   3. The method according to claim 1 or 2, characterized, that at least one longitudinal groove with a width of substantially the diameter of the insertion wire and a depth of essentially in the range of 0.7 to 1.0 times the diameter knife of the insertion wire is rolled. 4. The method according to claim 2, characterized, that the multi-layer jacket made from a prefabricated more layered clad tape is formed. 5.Wire-shaped welding electrode consisting of metals and / or alloys further consisting of a layered composite wire with an outer sheath 1 closed by welding made of ductile material and a cold-formable core wire 2 made of copper or copper alloys arranged inside the sheath 1 , produced by a method according to a of claims 1 to 4, characterized by a core with a mechanically integrated aluminum component with a mass percentage of ≧ 7.5 and / or a mechanically integrated iron component with a mass percentage of ≧ 1.5, the core ( 6 ) at least one Longitudinal groove ( 9 ) for receiving at least one insert wire ( 5 ) made of iron or iron alloys and an inner sheath ( 3 ) made of aluminum or an aluminum alloy based on the overall arrangement.